Virgo Logbook

Reports 1-1 of 1

AdV-INJ (Electro optical modulation system (EOM))

gosselin, masserot - 12:04 Monday 18 December 2023 (62774)

EOM 56MHz noisy

As observed in the logbook 64754, the EOM_56MHz amplitude seems more noisy as its noise can be see by the demodulation board .

This plot show its trend over one month , from 2023-11-15 to 2023-11-18, and the Injection Electronic room temperature .

Yesterday the Injection Electronic room temperature has been reduced from 22 to 17 degrees : after this temperature reduction the glitches on the INJ_EOM_56MHz_mag channel are not anymore visible ( see this plot )

Images attached to this report

62774_1702897045_LNFS_EOM_56MHz_mag-20231115-20231217.png

62774_1702897053_LNFS_EOM_56MHz_mag-20231216-20231218.png

Comments to this report:

Paoletti - 9:18 Tuesday 19 December 2023 (62785)

Yesterday night we restored the temperature setpoint int the IER.

The temperature is taking a long time to recover and has not yet recovered the old point (it was ~20 degrees, dropped to 16, now it is ~19 degrees).

But the EOM_56MHz noise was present even when the temperature dropped to 18 degrees, even less. So if it was a "temperature-dependent noise," it should have popped up again.

At the time being, it seems that this is not the case.

Images attached to this comment